A composite electrode and its manufacturing method and uses

Abstract

The present invention provides a composite electrode and a manufacturing method and use thereof, including a current collector and an active layer disposed on the current collector, and further including an island-shaped conductive layer disposed on the surface of the active layer away from the current collector. By providing the island-shaped conductive layer to form a concave-convex interface on the surface of the active layer, the protruding island-shaped conductive material has a high specific surface area and high liquid absorption characteristics for storing electrolyte, and the concave space between the island-shaped conductive materials forms a rapid diffusion channel for the electrolyte, and can also absorb and store a certain amount of electrolyte at the same time. The above concave-convex interface structure effectively solves the problem of rapid cycling decline caused by insufficient electrolyte and the inability of the electrolyte to timely return to the central region of the battery pack.

Description

Technical Field

[0001] The present invention belongs to the technical field of new energy batteries, and relates to a composite electrode and a manufacturing method and use thereof. Background Art

[0002] Currently, lithium-ion batteries have been widely used in various portable electronic products, power tools, electric vehicles, and energy storage systems. In the face of increasingly severe global energy and environmental problems, lithium-ion batteries have gradually moved from mobile phones, laptops, digital cameras, and portable small appliances to the field of electric vehicle power. Especially as the market's requirement for energy density becomes higher and higher, more space inside the battery is filled with materials.

[0003] Research has found that as the energy density increases and the internal space utilization rate improves, under high filling amounts and high compaction conditions, the liquid absorption, liquid retention ability, and electrolyte diffusion rate of the electrode significantly decrease. As the cycle progresses, the electrolyte gradually consumes, which easily causes cycle dives. Especially as the cycle continues, the middle part of the electrode rebounds and thickens, the pressure on the battery cell increases, and the electrolyte is extruded during the charge and discharge process and cannot flow back into the battery cell in time, ultimately resulting in insufficient electrolyte in the middle part, which causes abnormal problems such as interface black spots and lithium deposition, resulting in a rapid cycle dive.

[0004] CN115548444A improves the electrolyte used for the silicon negative electrode, optimizes the mass ratio of fluoroethylene carbonate (FEC), thereby avoiding severe cycle expansion and gas generation caused by excessive FEC; avoiding cycle dives in the later stage caused by too little FEC; CN113161615A provides a non-aqueous electrolyte including two specific additives to improve the film-forming performance and film-forming strength on the silicon-carbon negative electrode, thereby inhibiting the reaction between the silicon-carbon negative electrode and organic solvents, and further improving the cycle performance and effectively improving cycle dives;

[0005] CN114420927A provides a sponge-like porous negative electrode material for transporting, and using this negative electrode material can effectively improve the infiltration of the electrolyte, relieve the cycle volume expansion, and is beneficial to improving the cycle stability and solving the diving problem; CN105514418A provides a single-crystal positive electrode material obtained by spray drying to solve the problem that there are gaps between the primary particles and secondary particles in the positive electrode materials synthesized in the prior art, and thus prevent volume expansion and material cracking during the cycle from the source, and further improve the cycle performance and inhibit the occurrence of cycle dives.

[0006] In addition to the above optimizations of the electrolyte and the cathode and anode materials themselves, CN106025369A provides a lithium-ion battery. By providing an insulating layer that can absorb and release the electrolyte between the battery cell and the outer casing, the absorbed electrolyte is continuously released and supplied to the battery cell, acting on the insertion and extraction of lithium ions during the charge and discharge cycles of the battery, solving the problem of capacity drop during the cycle due to lack of electrolyte, and thus improving the cycle life.

[0007] Currently, there is still a lack of a technical solution for improving the electrode sheets inside the battery cell to specifically solve the problems of abnormal phenomena such as black spots at the interface and lithium deposition, and rapid cycle drop due to insufficient electrolyte in the middle part of the electrode sheet. Summary of the Invention

[0008] In view of the problems existing in the prior art, the purpose of the present invention is to provide a composite electrode sheet, its manufacturing method and uses. By providing an island-shaped conductive layer on the active layer of the electrode sheet, it can absorb, store and diffuse the electrolyte simultaneously, and thus effectively solve the problem of rapid cycle drop caused by insufficient electrolyte and the inability of the electrolyte to flow back to the central area of the electrode group in time.

[0009] To achieve this purpose, the present invention adopts the following technical solutions:

[0010] In the first aspect, the present invention provides a composite electrode sheet, which includes a current collector and an active layer disposed on the current collector, and further includes an island-shaped conductive layer disposed on the surface of the active layer away from the current collector.

[0011] The present invention forms a concave-convex interface on the surface of the active layer by providing an island-shaped conductive layer. The protruding island-shaped conductive material has a high specific surface area and high liquid absorption characteristics for storing the electrolyte. The concave space between the island-shaped conductive materials forms a rapid diffusion channel for the electrolyte, and can also absorb and store a certain amount of electrolyte simultaneously. Through the cooperation of the above concave-convex interface structure, the problem of rapid cycle drop caused by insufficient electrolyte and the inability of the electrolyte to flow back to the central area of the electrode group in time is effectively solved.

[0012] The following are the preferred technical solutions of the present invention, but not the limitations of the technical solutions provided by the present invention. Through the following technical solutions, the technical purpose and beneficial effects of the present invention can be better achieved and realized.

[0013] As a preferred technical solution of the present invention, the island-shaped conductive layer is composed of conductive protrusions.

[0014] Preferably, the conductive protrusions are arranged in an array.

[0015] Preferably, the conductive material in the conductive protrusions includes any one or a combination of at least two of conductive carbon black, graphene, superconducting carbon black, SWCNT (single-walled carbon nanotube), or MWCNT (multi-walled carbon nanotube). Typical but non-limiting examples of the combination include the combination of conductive carbon black and graphene, the combination of conductive carbon black and superconducting carbon black, the combination of conductive carbon black and SWCNT, the combination of conductive carbon black and MWCNT, the combination of graphene and superconducting carbon black, the combination of graphene and SWCNT, the combination of graphene and MWCNT, or the combination of SWCNT and MWCNT.

[0016] Preferably, the shape of the orthographic projection of the conductive protrusions on the composite electrode includes any one or a combination of at least two of circular, star-shaped, or plum-blossom-shaped. Typical but non-limiting examples of the combination include the combination of circular and star-shaped, the combination of circular and plum-blossom-shaped, or the combination of star-shaped and plum-blossom-shaped.

[0017] Preferably, the shape of the orthographic projection of each conductive protrusion on the composite electrode is the same.

[0018] Preferably, the particle size of the orthographic projection of the conductive protrusions on the composite electrode is 80 - 100 μm, such as 80 μm, 81 μm, 82 μm, 83 μm, 84 μm, 85 μm, 86 μm, 87 μm, 88 μm, 89 μm, 90 μm, 91 μm, 92 μm, 93 μm, 94 μm, 95 μm, 96 μm, 97 μm, 98 μm, 99 μm, or 100 μm, etc., but not limited to the listed values. Other unlisted values within the above numerical range are equally applicable.

[0019] As a preferred technical solution of the present invention, the height of the conductive protrusions is greater than 0 μm and less than or equal to 5 μm. For example, it can be 0.1 μm, 0.3 μm, 0.5 μm, 0.7 μm, 0.9 μm, 1.2 μm, 1.5 μm, 1.8 μm, 2.1 μm, 2.4 μm, 2.7 μm, 3 μm, 3.3 μm, 3.6 μm, 3.9 μm, 4.2 μm, 4.5 μm, 4.8 μm, or 5 μm, etc., 2 - 3 μm, but not limited to the listed values. Other unlisted values within the above numerical range are equally applicable.

[0020] If the height of the conductive protrusions is too low, it will affect the liquid storage effect in the liquid storage area; if the height is too high, it will occupy a large space and affect the energy density of the battery.

[0021] Preferably, the shortest distance between two adjacent ones of the conductive protrusions is 0 to 1000 μm, such as 0 μm, 1 μm, 3 μm, 5 μm, 7 μm, 9 μm, 15 μm, 30 μm, 50 μm, 70 μm, 90 μm, 110 μm, 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm, 500 μm, 550 μm, 600 μm, 650 μm, 700 μm, 750 μm, 800 μm, 850 μm, 900 μm, 950 μm or 1000 μm, etc., but not limited to the listed values, and other unlisted values within the above numerical range are equally applicable.

[0022] Preferably, on the surface of the active layer where the island-shaped conductive layer is provided, the unoccupied space between the conductive protrusions forms a grid liquid storage area.

[0023] Preferably, when the shortest distance between two adjacent ones of the conductive protrusions is 0 μm, the grid liquid storage area is a dot-type grid liquid storage area.

[0024] Preferably, when the shortest distance between two adjacent ones of the conductive protrusions is not 0 μm, the grid liquid storage area is a stripe-type grid liquid storage area.

[0025] When the shortest distance between two adjacent conductive protrusions is 0 μm, it means that two adjacent conductive protrusions are in contact with each other. At this time, the spaces surrounded by multiple conductive protrusions are independent of each other, and all the spaces are arranged in a dot matrix, thus forming a dot-type grid liquid storage area; when the shortest distance between two adjacent conductive protrusions is not 0, the unoccupied spaces between the conductive protrusions are interconnected, similar to zebra stripes, thus forming a stripe-type grid liquid storage area.

[0026] It should be noted that the height of the conductive protrusion is equal to the depth of the grid liquid storage area, and the distance between the conductive protrusions affects the width of each gap or channel in the grid liquid storage area.

[0027] The island-shaped conductive layer described in the present invention refers to independent small islands separated from each other on the ocean. Specifically, the shape and size of each island (conductive protrusion) during manufacturing are controlled to a certain extent. Therefore, the shapes and sizes of the conductive protrusions can be controlled to be similar and arranged in an orderly manner, or the shapes and sizes of the conductive protrusions can be controlled to have a certain degree of randomness and not be completely the same. The key is that an effective liquid storage area can be formed between all the conductive protrusions.

[0028] As a preferred technical solution of the present invention, based on the mass of the active layer being 100%, the mass fraction of the active material in the active layer is 70% to 99.9%, such as 70%, 72%, 74%, 76%, 78%, 80%, 82%, 84%, 86%, 88%, 90%, 92%, 94%, 96%, 98% or 99.9%, etc., but not limited to the listed values, and other unlisted values within the above numerical range are equally applicable.

[0029] Preferably, based on the mass of the active layer being 100%, the mass fraction of the binder in the active layer is 0.01% to 15%, such as 0.01%, 0.03%, 0.05%, 0.07%, 0.1%, 0.3%, 0.5%, 0.7%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14% or 15%, etc., but not limited to the listed values, and other unlisted values within the above numerical range are equally applicable.

[0030] Preferably, based on the mass of the active layer being 100%, the mass fraction of the conductive agent in the active layer is 0.01% to 15%, such as 0.01%, 0.03%, 0.05%, 0.07%, 0.1%, 0.3%, 0.5%, 0.7%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14% or 15%, etc., but not limited to the listed values, and other unlisted values within the above numerical range are equally applicable.

[0031] Preferably, the compaction density of the active layer is 1.8 to 3.8 g / cm 3 , such as 1.8 g / cm 3 , 2 g / cm 3 , 2.2 g / cm 3 , 2.4 g / cm 3 , 2.6 g / cm 3 , 2.8 g / cm 3 , 3 g / cm 3 , 3.2 g / cm 3 , 3.4 g / cm 3 , 3.6 g / cm or 3.8 g / cm 3 etc., but not limited to the listed values, and other unlisted values within the above numerical range are equally applicable.

[0032] In a second aspect, the present invention provides a method for manufacturing the composite electrode sheet described in the first aspect, and the manufacturing method includes:

[0033] Prepare an active layer on a current collector, and then spray a conductive paste on the surface of the active layer away from the current collector to form an island-shaped conductive layer.

[0034] The island-shaped conductive layer of the present invention can be disposed on the positive active layer or on the negative active layer, and has good adaptability to the active materials in each active layer. Therefore, the present invention does not limit the selection of specific active materials in the positive active layer or the negative active layer. For example, the positive active material in the positive active layer can be selected from ternary materials and / or lithium iron phosphate, wherein the ternary material includes any one or at least two combinations of NCM materials, NMX low-cobalt materials or NCX cobalt-free materials.

[0035] As a preferred technical solution of the present invention, the active layer is prepared by coating an active paste on a current collector.

[0036] Preferably, based on the mass of the active layer being 100%, the mass fraction of the active material in the active layer is 70% to 99.9%, such as 70%, 72%, 74%, 76%, 78%, 80%, 82%, 84%, 86%, 88%, 90%, 92%, 94%, 96%, 98% or 99.9%, etc., but is not limited to the listed values, and other unlisted values within the above numerical range are equally applicable.

[0037] Preferably, based on the mass of the active layer being 100%, the mass fraction of the binder in the active layer is 0.01% to 15%, such as 0.01%, 0.03%, 0.05%, 0.07%, 0.1%, 0.3%, 0.5%, 0.7%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14% or 15%, etc., but is not limited to the listed values, and other unlisted values within the above numerical range are equally applicable.

[0038] Preferably, based on the mass of the active layer being 100%, the mass fraction of the conductive agent in the active layer is 0.01% to 15%, such as 0.01%, 0.03%, 0.05%, 0.07%, 0.1%, 0.3%, 0.5%, 0.7%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14% or 15%, etc., but is not limited to the listed values, and other unlisted values within the above numerical range are equally applicable.

[0039] As a preferred technical solution of the present invention, before spraying the island-shaped conductive layer, roll press the active layer; or after spraying the island-shaped conductive layer, roll press the active layer and the island-shaped conductive layer simultaneously.

[0040] Preferably, the compaction density of the active layer is 1.8 to 3.8 g / cm 3 , such as 1.8 g / cm 3 , 2 g / cm 3 , 2.2 g / cm 3 , 2.4 g / cm 3 , 2.6 g / cm 3 , 2.8 g / cm 3 , 3 g / cm 3 , 3.2 g / cm 3 , 3.4 g / cm 3 , 3.6 g / cm or 3.8 g / cm 3 etc., but not limited to the listed values, and other unlisted values within the above numerical range are equally applicable.

[0041] As a preferred technical solution of the present invention, the thickness of the conductive paste is greater than 0 μm and less than or equal to 5 μm. For example, it can be 0.1 μm, 0.3 μm, 0.5 μm, 0.7 μm, 0.9 μm, 1.2 μm, 1.5 μm, 1.8 μm, 2.1 μm, 2.4 μm, 2.7 μm, 3 μm, 3.3 μm, 3.6 μm, 3.9 μm, 4.2 μm, 4.5 μm, 4.8 μm or 5 μm, etc. Preferably, it is 2 to 3 μm, but not limited to the listed values, and other unlisted values within the above numerical range are equally applicable.

[0042] Preferably, the conductive material component in the conductive paste includes any one or a combination of at least two of conductive carbon black, graphene, superconducting carbon black, SWCNT or MWCNT. For example, a combination of conductive carbon black and graphene, a combination of conductive carbon black and superconducting carbon black, a combination of conductive carbon black and SWCNT, a combination of conductive carbon black and MWCNT, a combination of graphene and superconducting carbon black, a combination of graphene and SWCNT, a combination of graphene and MWCNT or a combination of SWCNT and MWCNT.

[0043] Preferably, the spraying is carried out using a diaphragm spraying device.

[0044] Preferably, the diaphragm spraying device is a rotary spraying machine.

[0045] When the diaphragm spraying device used in the present invention sprays the conductive paste, the control of its dimensional parameters is close to the particle size of the finally formed conductive protrusions. For example, the thickness of the conductive paste is basically the same as or close to the height of the conductive protrusions.

[0046] In a third aspect, the present invention provides an ion battery, and the ion battery contains the composite electrode sheet described in the first aspect or the composite electrode sheet obtained by the manufacturing method described in the second aspect.

[0047] Fourthly, the present invention provides an electrical device, and the electrical device contains the ion battery described in the third aspect.

[0048] Compared with the prior art solutions, the present invention has at least the following beneficial effects:

[0049] The present invention forms a concave-convex interface on the surface of the active layer by arranging an island-shaped conductive layer. The protruding island-shaped conductive material has a high specific surface area and high liquid absorption characteristics for storing the electrolyte. The concave space between the island-shaped conductive materials forms a rapid diffusion channel for the electrolyte, and can also absorb and store a certain amount of electrolyte at the same time. Through the cooperation of the above concave-convex interface structure, the problem of rapid cycling dive caused by insufficient electrolyte and the inability of the electrolyte to flow back to the center area of the electrode group in time is effectively solved. Description of the Drawings

[0050] Figure 1 is a top view schematic diagram of the island-shaped conductive layer in the composite electrode obtained in Example 1;

[0051] Figure 2 is a cycling test chart of the electrodes obtained in Example 1 and Comparative Example 1;

[0052] Among them, 1 - active layer, 2 - conductive protrusion, 3 - tab. Detailed Embodiments

[0053] The technical solutions of the present invention will be further described below through specific embodiments.

[0054] Those skilled in the art should understand that the embodiments are only helpful for understanding the present invention and should not be regarded as specific limitations on the present invention.

[0055] Example 1

[0056] This example provides a composite electrode, as Figure 1 shown. The composite electrode is a positive electrode, and the composite electrode includes a current collector and an active layer 1 provided on the current collector, and further includes an island-shaped conductive layer provided on the surface of the active layer 1 away from the current collector; a tab 3 is provided on the composite electrode;

[0057] The current collector is an aluminum foil; the active material in the active layer 1 is NCM613 ternary material; the compaction density of the active layer 1 is 3.4 g / cm 3 ;

[0058] The island-shaped conductive layer is composed of conductive protrusions 2 arranged in an array; the conductive material in the conductive protrusions 2 is conductive carbon black; the shape of the orthographic projection of the conductive protrusions 2 on the composite electrode is a heptagonal star, and the particle size of the orthographic projection is between 80 and 100 μm. The height of the conductive protrusions 2 is 3 μm, and the shortest distance between two adjacent conductive protrusions 2 is 500 μm. The unoccupied space between the conductive protrusions 2 forms a striped grid liquid storage area.

[0059] This embodiment also provides a manufacturing method of the composite electrode, including the following steps:

[0060] (1) Take 9.65 kg of NCM613 ternary material, add 0.2 kg of conductive agent, including 0.15 kg of Sp (conductive carbon black) and 0.05 kg of CNTs (carbon nanotubes), add 0.15 kg of binder PVDF (polyvinylidene fluoride), and homogenize evenly in a PD mixer (double planetary mixer) to ensure that the fineness is ≤ 20 μm and the viscosity is 4000 - 6000 mPa·s to form an active slurry.

[0061] (2) After passing the active slurry obtained in step (1) through a 200-mesh sieve, coat it on the current collector at a surface density of 380 g / m 2 to form an active layer; roll press the active layer to make the compaction density of the active layer reach 3.4 g / cm3.

[0062] (3) Spray the conductive slurry of step (1) on the rolled active layer in step (2) using a rotary sprayer to prepare an island-shaped active layer and obtain a composite electrode.

[0063] Example 2

[0064] This embodiment provides a composite electrode. The composite electrode is a positive electrode. Except that the height of the conductive protrusions is adjusted from 3 μm to 0.5 μm, other conditions are exactly the same as those in Example 1.

[0065] Example 3

[0066] This embodiment provides a composite electrode. The composite electrode is a positive electrode. Except that the height of the conductive protrusions is adjusted from 3 μm to 5 μm, other conditions are exactly the same as those in Example 1.

[0067] Example 4

[0068] This embodiment provides a composite electrode. The composite electrode is a positive electrode. Except that the height of the conductive protrusions is adjusted from 3 μm to 6 μm, other conditions are exactly the same as those in Example 1.

[0069] Example 5

[0070] This embodiment provides a composite electrode sheet. The composite electrode sheet is a positive electrode sheet. Except that the shortest distance between adjacent two of the conductive protrusions is adjusted from 500 μm to 0 μm, so that the unoccupied space between each conductive protrusion forms a dot-type grid liquid storage area, other conditions are exactly the same as those in Embodiment 1.

[0071] Embodiment 6

[0072] This embodiment provides a composite electrode sheet. The composite electrode sheet is a positive electrode sheet. Except that the shortest distance between adjacent two of the conductive protrusions is adjusted from 500 μm to 260 μm, other conditions are exactly the same as those in Embodiment 1.

[0073] Embodiment 7

[0074] This embodiment provides a composite electrode sheet. The composite electrode sheet is a positive electrode sheet. Except that the shortest distance between adjacent two of the conductive protrusions is adjusted from 500 μm to 750 μm, other conditions are exactly the same as those in Embodiment 1.

[0075] Embodiment 8

[0076] This embodiment provides a composite electrode sheet. The composite electrode sheet is a positive electrode sheet. Except that the shortest distance between adjacent two of the conductive protrusions is adjusted from 500 μm to 1000 μm, other conditions are exactly the same as those in Embodiment 1.

[0077] Embodiment 9

[0078] This embodiment provides a composite electrode sheet. The composite electrode sheet is a positive electrode sheet. Except that the shortest distance between adjacent two of the conductive protrusions is adjusted from 500 μm to 1100 μm, other conditions are exactly the same as those in Embodiment 1.

[0079] Comparative Example 1

[0080] This comparative example provides a positive electrode sheet. The positive electrode sheet includes a current collector and an active layer provided on the current collector, but an island-shaped conductive layer is not provided on the active layer. Except for this, other conditions are exactly the same as those in Embodiment 1.

[0081] Assemble the batteries synchronously with the corresponding conventional commercial electrode sheets for each of the embodiments and comparative examples. After the formation and formation and grading are completed, perform a cyclic stability test according to 1C / 1C 100% DOD. The test results are shown in Table 1.

[0082] Table 1

[0083]

[0084] As can be seen from Table 1:

[0085] (1) Comparing Example 1 with Comparative Example 1: Figure 1 It is a cyclic test chart of Example 1 and Comparative Example 1. It can be seen that the composite electrode of Example 1 significantly improves the cycling stability in the later stage of cycling;

[0086] (2) Comparing Example 1 with Examples 2-4: As the height of the conductive protrusion increases, the cycling stability first increases and then basically remains unchanged, indicating that a conductive protrusion height of ≥3 μm can form an electrolyte demand that meets the full life cycle of the battery and can provide a smooth channel for the electrolyte reflux during the charge and discharge process;

[0087] (3) Comparing Example 1 with Examples 5-9: As the spacing of the conductive protrusions increases, the cycling stability first increases and then gradually deteriorates, indicating that a spacing of about 500 μm can provide an optimal electrolyte storage space and reflux channel to improve the cycling stability.

[0088] The present invention uses the above embodiments to illustrate the detailed structural features of the present invention. However, the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvement of the present invention, the equivalent replacement of the components selected by the present invention, the addition of auxiliary components, and the selection of specific methods, etc., all fall within the protection scope and the disclosure scope of the present invention.

[0089] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0090] In addition, it should be noted that, in the case of no contradiction, the various specific technical features described in the above specific embodiments can be combined in any suitable manner. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0091] In addition, any combination can be made between different embodiments of the present invention as long as it does not violate the idea of the present invention, and it should also be regarded as the content disclosed by the present invention.

Claims

1. A composite electrode, characterized in that, the composite electrode includes a current collector and an active layer disposed on the current collector, and further includes an island-shaped conductive layer disposed on the surface of the active layer away from the current collector; the island-shaped conductive layer is composed of conductive protrusions, and the conductive material in the conductive protrusions includes any one or a combination of at least two of conductive carbon black, graphene, superconducting carbon black, SWCNT or MWCNT; the shape of the positive projection of the conductive protrusions on the composite electrode includes any one or a combination of at least two of circular, star-shaped or plum blossom-shaped; the particle size of the positive projection of the conductive protrusions on the composite electrode is 80-100 μm; the height of the conductive protrusions is 2-3 μm, and the shortest distance between adjacent two conductive protrusions is 200-950 μm; on the surface of the active layer where the island-shaped conductive layer is disposed, the unoccupied space between each conductive protrusion forms a grid liquid storage area, and the grid liquid storage area is a striped grid liquid storage area; Based on the mass of the active layer being 100%, the mass fraction of the active material in the active layer is 70% to 99.9%; the mass fraction of the binder in the active layer is 0.01% to 15%; the mass fraction of the conductive agent in the active layer is 0.01% to 15%; the compaction density of the active layer is 1.8 to 3.8 g / cm 3 .

2. The composite electrode according to claim 1, characterized in that, the conductive protrusions are arranged in an array.

3. A manufacturing method of the composite electrode according to claim 1 or 2, characterized in that, the manufacturing method includes: preparing an active layer on a current collector, and then spraying a conductive paste on the surface of the active layer away from the current collector to form an island-shaped conductive layer; the thickness of the conductive paste is 2-3 μm; the conductive material components in the conductive paste include any one or a combination of at least two of carbon black, graphene, superconducting carbon black, SWCNT or MWCNT; Based on the mass of the active layer being 100%, the mass fraction of the active material in the active layer is 70% to 99.9%; the mass fraction of the binder in the active layer is 0.01% to 15%; the mass fraction of the conductive agent in the active layer is 0.01% to 15%; the compaction density of the active layer is 1.8 to 3.8 g / cm 3 .

4. The manufacturing method of the composite electrode according to claim 3, characterized in that, the active layer is obtained by coating an active paste on a current collector.

5. The manufacturing method of the composite electrode according to claim 3, characterized in that, before spraying the island-shaped conductive layer, roll-press the active layer; or after spraying the island-shaped conductive layer, roll-press the active layer and the island-shaped conductive layer simultaneously.

6. The manufacturing method of the composite electrode according to claim 3, characterized in that, the spraying is carried out by using a diaphragm spraying device.

7. The manufacturing method of the composite electrode according to claim 6, characterized in that, the diaphragm spraying device is a rotary spraying machine.

8. An ion battery, characterized in that, the ion battery contains the composite electrode according to any one of claims 1-2 or the composite electrode obtained by the manufacturing method according to any one of claims 3-7.

9. An electrical device, characterized in that, the electrical device contains the ion battery according to claim 8.

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